Compositions containing a blend of polycarbonate and ABS were disclosed in U.S. Pat. Nos. 3,130,177 and 3,852,393. Similar compositions were disclosed in U.S. Pat. Nos. 3,954,905 and 3,988,389 to possess improved weld line strength.
Improved impact strength of polycarbonates by the incorporation of a graft elastomer has been the subject of numerous U.S. Patents, for instance, U.S. Pat. Nos. 4,299,928, 4,245,058, U.S. Pat. No. Re. 28,723, U.S. Pat. Nos. 4,263,416, 4,263,415, 4,260,693 and 4,082,895 among others.